Do Ahead Chicken Casserole - cooking recipe

Ingredients

4 cups diced cooked chicken
9 slices bread (White or whole wheat, thick slices)
1/4 cup butter or 1/4 cup margarine
4 tablespoons butter or 4 tablespoons margarine
8 ounces fresh mushrooms, sliced
1 (8 ounce) can sliced water chestnuts, drained
1 (2 ounce) jar pimientos or 2 ounces sweet red peppers, cut in small strips
1/2 cup mayonnaise (lite is OK)
3/4 cup cheddar cheese, grated
1/4 cup flour
2 cups chicken broth
4 eggs, well beaten
2 cups milk
buttered breadcrumbs

Preparation

Lightly butter a 9x13-inch oven proof dish.
Cut crusts off the bread and save.
Place bread slices in a single layer in the bottom of the dish.
Put chicken on top.
Saute mushrooms in 2 tbsp butter and then put mushrooms on top of the chicken.
Sprinkle water chestnuts and pimentos on top of the mushrooms.
Dot with mayo and top with cheese.
Melt two tbsp butter in skillet, stir in flour until smooth.
Whisk in 2 cups broth, bring to a boil, whisking constantly until thickened, set aside.
Whisk milk and eggs together and pour over the cheese.
Spoon chicken broth sauce over the casserole.
Cover and refrigerate overnight.
Bring to room temperature and sprinkle with buttered crumbs (see below).
Bake in 350\u00b0F uncovered for 1-1 1/2 hours.
Buttered crumbs:
Crumble the crusts of the bread in crumbs.
Melt 1/4 cup butter add crumbs and toast for 10-15 minutes .
The crumbs can be made ahead and stored in a jar in the fridge.
Do not add crumbs to casserole until just before baking.